Sims earned his BS from Illinois State University. He went on to receive his MPA from the University of Illinois. He then earned his JD from Loyola University Chicago School of Law. He is an attorney for the Law Offices of Elgie R. Sims, Jr.

Sims was sworn into office on August 3, 2012 after Representative Constance A. Howard resigned in the face of federal investigations into an AIDS-awareness nonprofit that she founded.[1][2]